Normal and abnormal physiology, pharmacology, and anatomy of the gastroesophageal junction high-pressure zone

Possible technical aspects involved in the development of GERD after sleeve gastrectomy: Surgical technique considerations

Sleeve gastrectomy (SG) is the most common bariatric surgery worldwide and has shown to cause de novo or worsen symptoms of gastroesophageal reflux disease (GERD). Esophageal motility and physiology studies are mandatory in bariatric and foregut centers. The predisposing factors in post-SG patients are disruption of His angle, resection of gastric fold and gastric fundus, increased gastric pressure, resection of the gastric antrum, cutting of the sling fibers and pyloric spasm. There are symptomatic complications due to sleeve morphology as torsion, incisura angularis stenosis, kinking and dilated fundus. In this article, we present recommendations, surgical technique and patient selection flow diagram for SG and avoid de novo or worsening GERD.

Safety, efficacy, and selection strategy of laparoscopic local gastrectomy for gastrointestinal stromal tumors in the esophagogastric junction

Objective

To investigate the safety, efficacy, and selection strategy of laparoscopic local gastrectomy for stromal tumors in the esophagogastric junction.

Methods

Thirty-eight patients with mesenchymal tumors in the esophagogastric junction were retrospectively enrolled from April 2018 to July 2021 in which the upper edge of the tumor is less than 2 cm from the Z-line or has invaded the Z-line <1/2 circumference. Surgical outcomes, complications, recover, and postoperative gastroesophageal reflux of both groups were compared.

Results

27 patients underwent wedge resection, and 11 underwent resection by opening all of the layers of the stomach wall. Operative time (90.0 vs. 181.8 min, respectively, P = 0.001) was shorter for the WR group vs. RASW. Blood loss (20 vs. 50 ml, respectively, P = 0.012) was less for the WR group vs. RASW. Recovery of the RASW group was slower in terms of time to pass gas (2 vs. 3 days, P = 0.034), time to oral intake (2 vs. 4 days, P = 0.007), time to semi-liquid food intake (4 vs. 8 days, P = 0.003), and postoperative hospitalization (5 vs. 8 days, P = 0.001) vs. WR. In terms of short-term complications (≤30 days), no significant between-group differences were observed. Cardia stenosis did not occur in either group. In the WR group, one patient experienced mild reflux at 6 months and recovered 1 year after surgery. In the RASW group, one patient experienced severe gastroesophageal reflux at 6 months and 1 year after surgery, which was not entirely relieved by taking antacids. No other patients have gastroesophageal reflux.

Conclusion

Laparoscopic local gastrectomy is safe and feasible for mesenchymal tumors in the esophagogastric junction in which the upper edge of the tumor is less than 2 cm from the Z-line or has invaded the Z-line <1/2 circumference, and has achieved an excellent short-term effect. The choice of surgery is based on the relationship between the tumor and the position of the cardia.

Tissue engineering of the gastroesophageal junction

The gastroesophageal junction has been of clinical interest for some time due to its important role in preventing reflux of caustic stomach contents upward into the esophagus. Failure of this role has been identified as a key driver in gastroesophageal reflux disease, cancer of the lower esophagus, and aspiration-induced lung complications. Due to the large population burden and significant morbidity and mortality related to reflux barrier dysfunction, there is a pressing need to develop tissue engineering solutions which can replace diseased junctions. While good progress has been made in engineering the bodies of the esophagus and stomach, little has been done for the junction between the two. In this review, we discuss pertinent topics which should be considered as tissue engineers begin to address this anatomical region. The embryological development and adult anatomy and histology are discussed to provide context about the native structures which must be replicated. The roles of smooth muscle structures in the esophagus and stomach, as well as the contribution of the diaphragm to normal anti-reflux function are then examined. Finally, engineering considerations including mechanics and current progress in the field of tissue engineering are presented.

Innovations in Endoscopic Therapy for Gastroesophageal Reflux Disease

Minimally invasive endoscopic antireflux therapies are critical for bridging the gap between medical and surgical treatments for gastroesophageal reflux disease (GERD). Although multiple endoscopic devices have been developed, perhaps some of the most exciting options that are currently evolving are the full-thickness suturing techniques using widely available and low-cost platforms. Full-thickness endoscopic suturing can allow for a highly durable recreation of the anatomic and functional components of a lower esophageal sphincter, which are deficient in patients with GERD. Proper patient selection, endoscopic hiatal hernia evaluation, and standardized suturing methods are necessary to ensure success of endoscopic suturing for antireflux therapy.

Generation of Spontaneous Tone by Gastrointestinal Sphincters

An important feature of the gastrointestinal (GI) muscularis externa is its ability to generate phasic contractile activity. However, in some GI regions, a more sustained contraction, referred to as "tone," also occurs. Sphincters are muscles oriented in an annular manner that raise intraluminal pressure, thereby reducing or blocking the movement of luminal contents from one compartment to another. Spontaneous tone generation is often a feature of these muscles. Four distinct smooth muscle sphincters are present in the GI tract: the lower esophageal sphincter (LES), the pyloric sphincter (PS), the ileocecal sphincter (ICS), and the internal anal sphincter (IAS). This chapter examines how tone generation contributes to the functional behavior of these sphincters. Historically, tone was attributed to contractile activity arising directly from the properties of the smooth muscle cells. However, there is increasing evidence that interstitial cells of Cajal (ICC) play a significant role in tone generation in GI muscles. Indeed, ICC are present in each of the sphincters listed above. In this chapter, we explore various mechanisms that may contribute to tone generation in sphincters including: (1) summation of asynchronous phasic activity, (2) partial tetanus, (3) window current, and (4) myofilament sensitization. Importantly, the first two mechanisms involve tone generation through summation of phasic events. Thus, the historical distinction between "phasic" versus "tonic" smooth muscles in the GI tract requires revision. As described in this chapter, it is clear that the unique functional role of each sphincter in the GI tract is accompanied by a unique combination of contractile mechanisms.

[Anatomical features and biomechanical properties of the diaphragm in pathogenesis of hiatal hernia]

OBJECTIVE

To study changes of diaphragm and esophageal-diaphragmatic junction depending on age and constitutional features.

MATERIAL AND METHODS

We studied changes of diaphragm and esophageal-diaphragmatic junction depending on age and constitutional features by using of 40 cadaveric specimens (people aged 19-75 years).

RESULTS

Esophageal-aortic ligament is observed rarer with age. This ligament is poorly developed in brachiomorphic body type while diaphragmatic-cardiac ligament is generally absent as a rule. This is a predisposing factor for weakening this area. It was revealed that reduced strength and elasticity (especially esophageal-aortic and esophageal-diaphragmatic ligaments) is one of the key factors in the development of hiatal hernia. It is especially relevant for brachiomorphic body type, the 2^nd mature and elderly age. The 2^nd mature period is associated with reduced diameter and kinking of great arteries, that leads to 1.5-2 times decrease of arterial capacity of the diaphragm. Therefore, hiatal hernia repair using own tissues may be insufficient and accompanied by recurrence in persons with brachiomorphic body type in the 2^nd mature period.

CONCLUSION

Analysis of biomechanical data and anatomical features of the diaphragm may be useful to predict recurrent hiatal hernia.